Booster-valve for air-brakes.



W. V. TURNER. BOOSTER VALVE FOR AIR BRAKES. APPLICATION FILED JULY'3, 1915.

v WITNESSES "4E NORPPIS PETER: m. Fmmz-Lrnw" msnmamuI b. c.

Patented Apr. 10, 1917.

WALTER V. TURNER, OF EDGEWOOD,IENNSYLVANIA, ASSIGNOR TO THE WESTING HOUSE AIB BRAKE COMPANY, 035 WILMERDING, PENNSYLVANIA, A. CORPORATION OF PENNSYLVANIA.

BOOSTER-VALVE FOR- AIR-BRAKES.

Patented Apr. 10, 1917.,

Application filed July 3, 1915. Serial No. 37,892.

To all whom it may concern:

Be it known that I, WALTER V. TURNER, a citizen of the United States, residing at Edgewood, in the county of Allegheny and State of Pennsylvania, have invented new and useful Improvements in Booster-Valves for Air-Brakes, 01": which the following is a specification.

This invention relates to fluid pressure brakes, and more particularly to a brake apparatus for controlling the application and release of the brakes.

For-a given travel of the brake cylinder piston and with a predetermined auxiliary reservoir volume, the brake cylinder pressure obtained for a given reduction in brake pipe pressure will be fixed and if the brake cylinder volume be increased either by a direct increase in cylinder volume or indirectly as by the addition of piping or the like, then under the above conditions, the brake cylinder pressure will be correspondingly less.

An increase in brake cylinder volume may be compensated for by employing a larger auxiliary reservoir volume or by reducing the piston travel, but it is sometimes undesirable to accomplish the result in this manner.

The principal object of my invention is to provide means for obtaining a desired brake cylinder pressure for a given reduction in brake pipe pressure regardless of the brake cylinder volume and without increasing the auxiliary reservoir volume or reducing the brake cylinder piston travel.

In the accompanying drawing, the single figure illustrates a fluid pressure brake apparatus in section, with my improvement embodied therein.

My invention may be applied to various types of brake controlling valve devices and in the drawing as shown in connection with an ordinary triple valve device comprising a casing 1 having a piston chamber 2 connected to brake pipe 3 and containing piston 4.

Valvechamber 5 at one side of piston 4 is connected by pipe 6 to auxiliary reservoir 7 and contains the usual main slide valve 8 and graduating valve 9 adapted to be operated by piston 11.

The valve device for boosting the pressure in the brake cylinder may comprise a casing 10 adapted to be secured to the triple valve casing and having a piston chamber 11 containing a piston 12 and a valve chamber 13 containing a slide valve 14: adapted to be operated by the piston 12. A second e11- larged piston 15 is provided with a stem 16 adapted to engage the piston 12, and has a chamber 32 at one side, which communicates with a passage 17 I The piston 12 is provided with a seat 18 and 1s normally held in the seated position by a spring stop 19, subject to the pressure of a spring 20.

The valve chamber 13 is open to a supplemental reservoir 21 through pipe 22 and passage 23 containing a non-return ball check valve 2 1. v

The booster valve casing 10 also contains a valve piston 25 subject on one side to brake cylinder pressure supplied-from the brake cylinder 26 through pipe 27 and passage 28 and on the opposite side to the pressure of a spring 29, the spring chamber 30 being open to the atmosphere through a passage 31.

In operation, fluid supplied to the brake pipe 3 flows to piston chamber 2 and through the usual feed groove 33 to valve chamber 5, charging the auxiliary reservoir 7. The supplemental reservoir 21 is charged from valve chamber 5 through a port 3 1 in the slide valve 8 which registers in release position of the valve with a passage 35, opening into passage 23.

Fluid is then supplied from the supplemental reservoir 21 through passage 23 to valve chamber 13.

If the brake pipe pressure is reduced to effect an application of the brakes, the triple valve parts move out, so that service port 36 registers with passage 37 which opens into passage 1 Fluid from the auxiliary reservoir 7 will then be admitted to thepiston chamber 32.

Chamber 38 at the opposite side of piston 15 is subject to the fluid at brake cylinder pressure supplied through passages 28 and 39,'the stem 16 being a loose fit in its guide bearing, and since the brake cylinder is now at atmospheric pressure, the piston 15 will be promptly actuated by the auxiliary reservoir pressure, so as to efi'ect the movement of the piston 12 and the slide valve 14. By this movement, ports 40 in the valve 1d are brought into registry with branches of a passage 4:1 connected by pipe 42 to the brake cylinder 26, soithat fluid is supplied from In releasing the brakes, upon movement the supplemental reservoir 21 to the brake of the triple valve parts to release position,

7 cylinder. passage 37 will be connected through cavity While fluid is being thus supplied from in slide valve 8 with cavity port 46 the supplemental reservoir to the brake cyl' and fluid from the brake cylinder will then inder, the usual communication from the exhaust through passages 28 and 39, lifting 7o auxiliary reservoir to the brake cylinder is check valve 47. WVith the release of brake cut oflrbythe valve piston 25. cylinder pressure, the spring 29 operates to The movement of the slide valve 14 to return the valve piston 25 to its normal open the ports for supplying fluid from the position. supplemental reservoir to the brake cylinder Having now described my invention, what also uncovers a passage 43, leading to spring I claim as new and desire to secure by Letchamber 30, and having a' branch passage ters Patent, is:

leading to the chamber 38 below the piston 1. In a fluid pressure brake, the combina- 15, so that fluid from the supplemental restion with a brake cylinder, auxiliary reserunderside of the valve piston 25 will overreservoir to the brake cylinder. come the resistance of spring 29 and said 2. In a fluid pressure brake, the combinaervoir can flow to said chambers, but since voir, and an additional source of fluid under chamber 30 is open to exhaust port 31, the pressure, of means operating in a service pressure in the chamber. 38 can not build up, application of the brakes for supplying fluid andthe parts will therefore remain in open from said additional source of fluid under position; f i 7 pressure to the brake cylinder and adapted When the brake cylinder pressure has upon a predetermined increase in brake cylbeen increased to a predetermined degree by inder pressure to cut ofl the supply from flow from the supplemental reservoir, the the additional source and open communicabrake cylinder pressure which acts on the tion for supplying fluid from the auxiliary valve piston will then be shifted upwardly tion With a brake cylinder, auxiliary reserso as to uncover passage 44 and thus permit voir, and an additional source of fluid under flow from the auxiliary reservoir to the pressure, of means operating upon a service brake cylinder through passages 37, 4A, and application of the brakes for first supplying 28. This movement of thevalve piston 25 fluid from the additional source of fluid unalso closes passage 43, so that fluid from der pressure to the brake cylinder with comthe supplemental reservoir can no longer munication from the auxiliary reservoir cut vent at the exhaust port 31. The pressure in off and then adapted upon a predetermined the chamber 38 will then build up instantly increase in brake cylinder pressure to cut oif to supplemental reservoir pressure and since the supply from the additional source and the piston chamber32 is now open to the open communication for supplying fluid brake cylinder, the higher supplemental resfrom the auxiliary. reservoir to the brake ervoir pressure operates the piston 15 and cylinder.

permits the spring 20 to return the valve 14 3. In a fluid pressure brake, the combina- 5 to the closed position, in which the supply tion witha brake pipe, brake cylinder, auxilof fluid from the supplemental reservoir to iary reservoir, supplemental reservoir, and

r the brake cylinder'is cut off. a valve device operated upon a gradual re- It will thus be seen that in making a servduction'in brake plpe pressure for supplying ice application of the brakes, fluid is first fluid from the auxiliary reservoir to the 1 0 supplied from the supplemental reservoir to brake cylinder, of means for first supplying the brake cylinder until the brake cylinder fluid from the supplemental reservoir to the pressure has been built up to a predeterbrake cylinder with communication from mined degree, While communication from the auxiliary reservoir to the brake cylinder the auxiliary reservoir to the brake cylinder cut oil and then adapted to cut off the supis cut off, and then the supply from the supply from the supplemental reservoir to the plemental reservoir is cut off and communibrake cylinder and open communication for cation is opened for supplying fluid from supplying fluid from the auxiliary reservoir the auxiliary reservoir. Since no fluid is. to the brake cylinder. taken from the auxiliary reservoir during 4. In a fluid pressure brake, the combina- 2. the period that fluid is supplied from the tion with an auxiliary reservoir, brake cylsupplemental reservoir, the full pressure of inder, and a supplemental reservoir northe auxiliary reservoir is retained for gradu mally charged with fluid under pressure,

ally increasing the brake cylinder pressure of a valve mechanism operated by flow of in the usual way upon further reductions in air from the auxiliary reservoir in applying 5 brake pipe pressure, so that the usual size the brakes for opening communication from "auxiliary reservoirmay be employed to obthe supplemental reservoir to the brake cyltain the desired brakecylinder pressuresin inder and means operated upon a predeterspite of any lncrease 1n brake cylinder volmined increase in brake cylinder pressure ume due to piping and the like. for opening communication from the auxiliary reservoir to the brake cylinder and for effecting the operation of said valve mechanism to cut off the supply of fluid from the supplemental reservoir to the brake cylinder.

5. In a fluid pressure brake, the combination with a brake cylinder, auxiliary reservoir, a supplemental reservoir normally charged with fluid under pressure, a brake pipe, and a valve device operated upon a reduction in brake pipe pressure for supplying fluid from the auxiliary reservoir to the brake cylinder, of a valve mechanism operated by the flow of fluid from the auxiliary reservoir in applying the brakes for opening communication from the supplemental reservoir to the brake cylinder and means normally closing communication from the auxiliary reservoir to the brake cylinder and operated upon a predetermined increase in brake cylinder pressure for opening said communication and for varying the fluid pressure on said valve mechanism to operate same and thereby cut oii communication from the supplemental reservoir to the brake cylinder.

In testimony whereof I have hereunto set my hand.

WALTER V. TURNER.

Witnesses: A. M. Grammars, BARBARA HERBERT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

